GAS JET NOISE MUFFLER (VERSIONS) Russian patent published in 2009 - IPC F01N1/14 

FIELD: engines and pumps.

SUBSTANCE: invention relates to gas jet noise mufflers, mainly of gas turbine engines. The proposed noise muffler comprises a cylindrical ejector adapter coated with noise-absorbing material and incorporating a flow passage element representing a bundle of cylindrical tubes diverging along the gas flow from the center to the edges. The above cylindrical tubes are rigidly interconnected, while the flow passage element is attached to the said cylindrical ejector element inner surface with the help of at least three spokes, located in the plane perpendicular to the ejector adapter axis. The following materials can be used as the said noise-absorbing materials, i.e. the "Rockwool"-type basalt-based mineral cotton, or "URSA"-type mineral cotton, or the P-75 basalt cotton, or glass wool coated with glass felt, or foamed polymer, e.g. polyethylene or polypropylene, or a material based on aluminium-containing alloys and subjected to subsequent filling with titanium hydride or with air with density varying from 0.5 to 0.9 kg/m³ and that feature the following mechanical properties, i.e. compressive strength of 5 to 10 MPa, bending strength of 10 to 20 MPa. The afore mentioned noise-absorbing material is completely coated by acoustically transparent material, for example, glass fabric EZ-100 or "Poviden"-type polymer. As well cited are some other versions of the noise-absorbing material.

EFFECT: higher muffler acoustic efficiency.

4 cl; 3 dwg